Power modules without a baseplate: a reliable and cost-effective solution
Power modules serve a wide and diverse range of purposes. For some applications, power density is a key factor. For others, efficiency or price may be the sticking point. But for all applications, reliability is a top priority.
Modules with solid baseplates made of copper or aluminum silicon carbide are commonplace. Cost concerns have also given rise to a new breed of module without a baseplate. The Figure shows a flow 0 module without a baseplate using direct bonded copper (DBC), and a flow 2 module with a baseplate.
Flow 0 direct bonded copper without a baseplate (upper)
and flow 2 with a copper baseplate (lower)
DBC substrates have proven their merits in power electronic applications over many years. The advantages of DBC substrates are many: They can handle high temperatures and current. Their coefficient of thermal expansion (CTE) is a good match for that of silicon. They isolate high voltages and show low capacitance between the front and back sides.
When several aluminum oxide DBC substrates are used, they are often soldered to an additional baseplate. For some large modules equipped with a rectifier, brake, and an inverter, the rectifier and brake are soldered to one substrate, and the inverter IGBTs and freewheeling diodes to another.
AlSiC (aluminum silicon carbide) baseplates are often used for traction applications in place of copper plates. The materials have very different physical properties, with the CTE and thermal resistance being the key factors.
This article looks as various thermal and reliability aspects of power modules with and without baseplates, including:
●The coefficient of thermal expansion
●The reliability of different approaches
●The influence of thermal spreading
“Modules without a baseplate: a reliable and cost-effective solution” includes cross-section diagrams, microphotographs, and numerical tables to explain the situation, and is presented as a pdf document.
About the author
Patrick Baginski is a Field Application Engineer at Vincotech GmbH, an independent operating unit within Mitsubishi Electric Corporation.
- No news
- Volvo evaluates flywheel hybrid drive - fuel savings of up to 25%
- PV storage market is set to grow to USD19bn by 2017
- Ultra-low-power SoC supports world's smallest Bluetooth location stickers
- Power-One enters into patent license agreement with Microchip
- Quad-MOSFET solution boosts efficiency and eliminates heat sinking in active bridge applications
- Solar industry capital spending hits seven-year low in 2013 but upturn is on the cards
- Market for GaN and SiC power semiconductors set to rise by factor of 18 in next decade
- Imec and Renesas collaborate on ultra-low power short range radios
- Advanced microcontroller combines floating point and low leakage technology to achieve longest battery lifetime in portable applications
- World's lowest power Bluetooth smart chip is unveiled
- Dangers of Aftermarket Counterfeit Battery Packs
- High Voltage Surge Stoppers Ensure Reliable Operation During Power Surges
- Motor-Drive Design made Simple
- Adaptive Cell Converter Topology Enables Constant Efficiency in PFC Applications
- Micropower Isolated Flyback Converter with Input Voltage Range from 6V to 100V
- Derating of Schottky Diodes
- Heatsink Optimization
- High Performance ZVS Buck Regulator Removes Barriers To Increased Power Throughput
- Waste heat replaces batteries
- Stepper Motor Control IC